Saturday, December 31, 2011

Avastin®, Plan B®, and Magical Thinking

“Magical thinking” is believing something is true because you want it to be true even when there is strong evidence that it is not. It is normal in young children. They believe in Santa Claus and the Easter Bunny and conjurer’s tricks. This is in part because adults encourage them to, and because they do not know the evidence and they haven’t enough brain maturity to make the connections. Beyond a certain age, however, it is not normal. Yet we do it all the time.

It is common enough in politics, for sure. A wise expert (OK, me) once said “Data is only useful if it confirms your preconceived notions”. Otherwise, hearing the data that should demonstrate that you are wrong only confirms your pre-existing beliefs because it reminds you of why you believe it. The evidence is the evidence, and sometimes it is inconclusive and subject to different interpretations depending upon one’s perspective. That’s what makes horse races. Sometimes it is conclusive, but leads to a different conclusion than the one that you want to hear.

Religion is different; it is, by definition, based on faith. It becomes confusing, for me, when this is complicated by searching for evidence (e.g., the Catholic Church searching for evidence of a miracle in order to sanctify someone), but at bottom it is about faith. Some people have lost their faith in the religion in which they were brought up because of seeing contradictory evidence in the world, others have reconciled that evidence with their beliefs, others manage to separate the evidence from their faith, and still others reject all the evidence of their senses if it contradicts their faith. We have classic examples of this last, with lecturers in the early European medical schools reading from Aristotle on anatomy, ignoring the visual evidence provided by the cadavers being dissected in front of them that demonstrated that what Aristotle described was wrong. Luckily for anatomy and medicine, the schools were able to move on from this, in part because Aristotle, while revered, was not a Christian expert. It was rougher for Galileo when he demonstrated that the earth rotates around the sun.

I understand people’s interest in believing to be true things that the evidence demonstrates is not. It is comforting, it offers hope, and it can offer consistency. I wish, sometimes, I had more of it. My son died 9 years ago from completing suicide. If I believed that there was an afterlife, and that he was somewhere happily being cared for by my mother, who died over 30 years ago, it would make me feel better. After all, she was a wonderful, nurturing person, a kindergarten teacher who loved children, and she died just after he turned 2, so never got to see him grow up. It would be great to believe that they were getting to know and enjoy each other now. But I don’t.

Nonetheless, I am sure there are things that I believe that are contrary to the evidence. Certainly, things I believe that have conflicting evidence. Like that people are good, that the world can be a better place, that the ‘better angels’ of our nature may overcome selfishness and greed and hypocrisy and meanness. Sometimes that belief is sorely tried. It has been a particularly hard couple of years as the perpetrators of the greatest worldwide financial crisis have gotten off and maintained and increased their wealth while hundreds of millions of their victims have had their lives ruined, with no end in sight. And with whole cohorts of politicians and pundits advocating that these perpetrators be spared any penalty while slashing any programs that benefit their victims.

For most of us, and in most societies, there are limits to what we tolerate because of people’s beliefs. We do not, as a rule, accept that a false belief, a delusion, about another is an excuse for murder. Of course, if that false belief is on the part of the government that sends young people to war and to kill, it is accepted. And for many zealots, of many beliefs and causes, whether Islamic terrorists or anti-abortion murderers, there is a portion of the population who will accept it.

One group that has good reason to want to believe in things for which there is no evidence is those who are threatened with death from a disease for which there is no effective, “approved”, treatment. Cancer, for instance, or AIDS. In the 1980s and 1990s, AIDS advocacy groups pushed for quick FDA approval for drugs to fight a disease that was killing lots of people. To some degree it happened, and luckily those drugs were effective, and better drugs were developed, and today AIDS is most often a chronic disease. When a study showed that bevacizumab (Avastatin®), an anti-cancer drug created through recombinant DNA that had positive effect for some other cancers such as colorectal cancer, was also effective in prolonging the lives of women with metastatic breast cancer for a few months (not curing them), the large breast-cancer advocacy community pushed the FDA for early approval. It was approved. But then more studies appeared that showed it was not effective. Several of them. And the FDA, appropriately based upon the evidence, withdrew their approval. Blue Cross/Blue Shield of California then decided it wouldn’t pay for it. Yes, much of the motivation was financial – it costs $90,000 per year to treat a patient (except less, really, because few last a year), but it was based on the evidence. Would you pay $90,000 for a drug that didn’t work? How about spending that on treating someone else with a drug that doesn’t work? But having someone else pay for it for you (your insurance company and those other people who are paying premiums)is less painful. There was a big uproar. BC/BS (and Medicare) are now again paying $90,000 a year for treatment of breast cancer with a drug that doesn’t work.

On the other hand, kowtowing to true believers can have the opposite effect. It can lead to restricting access to a drug that does work. This has occurred recently with Plan B One-Step®, “the morning-after pill” which effectively provides emergency contraception if taken within 72 hours (maybe more) of unprotected intercourse. Approved for women 17 and over without a prescription, this form of the hormone levonorgestrel is kept “behind the counter” so those under 17 cannot get it. It doesn’t make sense, since girls under 17 can and do have unprotected sex and get pregnant. It is also safe. So, recently the FDA, examining all the evidence, recommended that it be made available without a prescription and sold “over the counter”. Then Secretary of HHS Kathleen Sebelius overruled, in an almost unprecedented action, the FDA’s recommendation. There was no science or evidence behind the Secretary’s action. Her stated reason, that younger women cannot understand the instructions, would, if one wanted to believe it, be an unreasonable standard. Can they understand the instructions to prevent adverse effects from ibuprofen or acetaminophen? Is the risk of pregnancy in these girls less than the risk from taking Plan B incorrectly? Nonsense. It is a political judgment, pandering to the belief of those who magically believe that because they don’t want young girls to have sex they won’t as long as contraception is not available to them to “encourage” it.

People read and support things that agree with what they think. I do not delude myself into thinking that what I write in this blog “converts” people; I recognize that people who read and like it probably already agree with me. But I do try to present evidence. And sometimes readers challenge me on my interpretation of the evidence (see, for example, the comments on Fluoridation: Dental health for all, October 26, 2011). One of the hardest things for physicians to do is to “un-learn”, to change the beliefs that they have had for years or decades when new information shows that what they believed is wrong. It is hard for them, and harder for the lay public, to understand that doing something was the right thing in the past because of the best evidence at the time, but is the wrong thing now. And what we think is the right thing now, based on the best evidence available, not be true in the future. That is how science evolves.

But magical thinking should have nothing to do with it.


Oh, yes. And in support of a tradition which Dilbert correctly points out is only a random point in time (and despite his use of "oxytocin" when he may have meant "oxycodone"):

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